Dry distillation of shale and other slate-shaped materials



Jan. 6, 1942. E. A. JoHANssoN v DRY DISTILLATION OF SHALE AND OTHER SLATE-SHAPED MATERIALS Filed Nov. 28, 1940 2 Sheets-Sheet l k3 [NVP/vier. fdr/)7 Anf/reas Jan. 6, 1942. E. A. JoHANssON DRY DISTILLATION OF SHALE AND OTHER SLATE-SHAPED MATERIALS 1940 2 Sheets-Sheet 2 Filed Nov. 28

.f MWI# MM MQW Patented Jan. 6, 1942 DRY DISTILLATI'ON OF SHALE 'AND OTHER SLATE-SHAPED MATERIALS Edvin Andreas Johansson, Stockholm, Sweden Application November Z8, 1940, Serial No. 367,492 In SwedenDecember 1, 1939 5 Claims. (Cl. 202-16) This invention relates to the dry distillation of materials occurring or obtained in the form of plates, slabs, slates or similar flatpieces', and. more particularly to the dry distillation of shale.

In the known art, the dry distillation of such materials is generally carried out infurnaces, such as tunnel furnaces,.through whichthe shale slates, etc., are `conveyed upon perforated carriers, for instance vWaggonsfwith perforated bot toms. In these furnaces the heating of the material is generally effected by means of the distillation gases produced in the process .which are, by means of fans, repeatedly forced through heating elementsl in which they are heated, and then through the material undergoing distillation.

`In this process difficulties are often encountered due to the fact that the vshale slabs or slates on charging, in greater or smaller portions ofk thev charge, take such positions that their flat sides offer a very great resistance against the circulation of gas through the material.

The present invention now provides a process by means of which said difficulties are completely removed. f f

According to the invention this is attained by charging the slate-shaped material, such as shale, in the transporting means or conveyors in tudinalY direction of theV furnace andv provided with anumber vof pipes passing, preferably substantially transversely, therethrough, which pipes, being intended to serve for the conveyance of distillation gases therethrough, have their openings directedto one of the perforated side Walls of the Waggons. Further said: chambers or l ducts arenalso provided withA inlets and outlets through the same furnace.

such a Way that the flat sides ofthe pieces take a substantially horizontal position, and by passing the distillation gases through the material thus charged in a substantially horizontal direction.

By this manner of Working the circulation of' the gases through the material to be Adistilled is considerably facilitated. 1

For carrying out the process according tothe invention a furnace, for instance a tunnel fur-y nace of the above-mentioned kind, may be used..

channels in such a way that the circulation ofv gas through the Waggons and the materialv therein will take place substantially horizontally.

Further the furnace is provided with means for indirect heating of the circulating distillation gases, comprising a number of pipes arranged inside the furnace. According to one embodiment of the invention said heating means consist of chambers or ducts arranged in the longifor heating gases, for instance ue gases, for passing the same around said pipes to heat the `distillating gases passing in the latter to the ldesired temperature. l

In another embodiment of the invention,- said pipes are arranged-in the longitudinal direction of the tunnel furnace and intended for the conveyance: of heating gases therethrough, while .the distillation gases circulate between and around said pipes and are thereby heated Other characterizing features of the invention will appear from the following description. with reference to the drawings where two 'different embodiments of the furnace according to the invention are illustrated by way of example.

Fig. 1 is -a vertical longitudinal section through a a tunnel furnace according. to the invention taken aflterline I--I in Fig. 2. f

Fig.: 2 is a horizontal longitudinal section Fig. 3 shows ona larger Scalea transverse sec*A tion taken on line IIIH-III of Fig. l.

Fig. 4 is a similar transverse section through a modification of the furnace.y f 1 l According torligs.-` l-SL the furnace consistsV of a longitudinally extending. tunnel I. Alt the ends f said tunnel is connected with an entering cham-- ber 2 andy a discharging chamber 3,` which can be closed ywith respect to the. tunnel by meansl of dampers 5.and 6 respectively. The material to be distilled, for instance yshale, is conveyed through the furnace charged in AWaggons 4.

The heatingA of the materialv is Leffected by means of flue. gases supplied through inlets 'I and 8 at the ends of the tunnel furnace and then conveyed in the longitudinal direction of the furnace in closed heating chambers or sections 9a and 9b respectively from which the gases lescape :through outlets It) and Il. Said heating sections 9a and y9b are providedwith a great'number of pipes I2 passing transversely through the sections, the ends of said pipes being connected lto the side walls of the sections 9a and. sb by welding or the like. Consequently, the flue gases supplied to said. sections 9o and 9b will circulate around the pipes f2..

The Waggons 4 with. the materiali to be distilled contained therein are .conveyed intermittingly through the furnace in direction from the left to the right. The vertical or upright standing side Walls I3, I4 of the Waggons are provided with a great, number of perforations or openings for the passage of the distillation gases. As

shown in Fig. 3, the Waggons are disposed and conveyed through the furnace alongside the heating sections 9a and 9b in such a way that a longitudinal space I5 is left between the walls I3 of the Waggons and the adjacent side Walls of said sections, and another longitudinal space I6 between the walls I4 of the Waggons and the opposite side wall of the tunnel. The space I5 is closed above by means of a wall I'I, and the space I6 is by means of a channel I8 connected with a chamber I9 between the other side walls of the heating sections 9a and 9b and the opposite wall of the tunnel.

The Waggons 4, space I5, pipes I2, chamber I9, channel I8 and space I6 form in the sequence now mentioned together a circulation chamber for the distillation gases which by means of fans 20 are circulated through the same in the direction indicated by the arrows.

Whenloa-ding the slate-shaped material, for instance shale, in the Waggons, the same is charged in such a way that the flat sides of the pieces take substantially horizontal positions, whereby they offer only a comparatively small resistance to the flow of the distillation gases transversely through the Waggons as described. The Waggons are preferably so constructed that their breadth is relatively small in comparison with their height. Below the Waggons shown in the drawings are provided with central wheels 2l which run on a single rail 22, and above they are kept in position by means of suitable guiding devices, for instance guide rolls 23.

The side walls I3, I4 of the Waggons are below provided With swing hatches 24 arranged on both sides of a rid-ge 25 at the bottom of the waggon. When the Waggons have been conveyed into the discharging chamber 3 and said hatches are opened, the -distillation residue, the coke, is discharged in two streams down into the shaft 26 from where it is conveyed, wholly or partly, to a fireplace 2l where vit is burned. From the iiue gases thereby generated the heating gases required for the distillation process are obtained. The distillation gases are discharged from the circulation chambers through pipes 28 and subjected to further treatment.

In the embodiment according to Figs. l-3 the fans 20 are arranged to suck-in the hot distillation gases passing out of the heating section and to force them through one of the perforated side Walls of the Waggons. But the fans may also beV arranged to circulate the gases in the opposite direction, that is to suck-in the comparatively cold distillation gases passing out of the Waggons and force them through th-e heating system.

According to Fig. 4, the heating system consists of a number of pipes 29 arranged in longitudinal direction of the furnace, through which the heating gases v(flue gases) are conveyed and between and around which the distillation gases are circulated, either in the -direction shown in the figure or in the opposite direction.

Instead of arranging the heating system only on one side of the Waggons, as described above and shown in the figures in the drawings, it is also possible to provide heating systems on both sid-es bymeans of distillation gases produced in the process, Which are in a heated state repeatedly circulated inside the furnace through said charge of material, the steps which consist in charging the slate-shaped material in such a way that the flat sides of the pieces take a substantially horizontal position, and passing the distillation gases through the material thus charged in a substantially horizontal direction.

2. Process for dry distillation of shale, which comprises charging the shale in perforated containers in suchv a Way that the flat sides of the shale pieces take a substantially horizontal position, conveying the containers thus charged through a distillation furnace of the tunnel furnace type, circulating distillation gases produced in the process repeatedly transversely inside the furnace and in a substantially horizontal direction through said containers and the charge of shale therein, said circulating distillation gases being indirectly heated after each passage through the shale charge, and withdrawing distillation products from the furnace.

3. Apparatus for dry distillation of shale, comprising, in combination, a furnace of the tunnel furnace type, containers for transporting the shale through the furnace having perforated side walls for circulation of ,distillation gases substantially horizontally through said containers, closed heating chambers inside the furnace in the longitudinal direction thereof provided with a number of pipes passing substantially transversely through said chambers for conveyance of the Vdistillation gases therethrough, said chambers being provided with inlets and outlets for heating gases for the heating of the distillation gases passing through said pipes, a baille wall for guiding the gases for horizontal passage through said containers and said pipes and ventilators for circulating said distillation gases in circuit through said containers and said heating means.

4. Apparatus for dry distillation of shale, comprising, in combination, a furnace of the tunnel furnace type, containers for transporting the shale through the furnace having perforated side Walls for circulation of distillation gases substantially horizontally through said containers, a system of pipes arranged inside the furnace in the longitudinal direction thereof for conveyance of heating gases therethrough, ventilators for circulating distillation gases transversely through said containers and said system of heating pipes between and around the pipes, and a baille Wall which guides the gases for horizontal passage through said containers and said system of heating pipes.

5. Apparatus for dry distillation of shale, comprising, in combination, a tunnel furnace, waggons for conveying the shale through the furnace having perforated side Walls adjacent to circulation chambers when the waggon travels through the furnace, for the circulation of distillation gases substantially horizontally through said Waggons, closed heating chambers arranged in the longitudinal direction of the furnace adjacent to said circulation Achambers and provided with a number of pipes passing substantially transversely through said chambers for conveyance of the distillation gases therethrough, saidv heating chambers being provided with inlets and outlets for passing heating gases through the same for heating of the distillation gases pass- 

